Can an AI agent leave a standing wish and be told when a matching listing appears?

Yes. The Isto Intents protocol is an open interface (CC BY 4.0) for standing purchase intents: an agent states once what a person wants — a used car, a home — and an intent holder, a listing portal for the person's country, keeps it and reports matching listings. The person confirms on the portal's own page.

Questions and answers

How does an agent connect?

Through one MCP server for every country, https://istointents.com/mcp (Streamable HTTP, no authentication), or over A2A at https://istointents.com/a2a. The tools are intent_publish_intent, intent_get_intent, intent_list_matches and intent_withdraw_intent. The binding: MCP.

Which holder receives the wish?

Only active holders in the registry that serve the person's country and category and accept forwarding. If one fits, it gets the wish; if several fit, the person chooses from them in a random order drawn for each request: how it chooses. Today Slovakia and Czechia are served.

Where are the person's contact details?

Never in the chat or in the protocol messages. The agent receives a confirmation link; the person types their e-mail only on the holder's own page, and nothing is watched before they confirm.

Can a listing portal become a holder?

Yes, on its own, free and without an account: publish a descriptor and an MCP server, check the host, submit it to the registry. A WordPress plugin and a PHP library are ready: join the registry.

Is this a payment or checkout protocol?

No. It ends where a purchase begins, and can sit beside checkout protocols: AP2 mandates.

Where is the explanation for buyers?

On istointents.com: can ChatGPT or Claude watch listings for me?